8 ms·

Today’s Smalltalk: A Second Look At The First OO Language

77 points by MarcusDenker 13y ago

informatimago 13y ago
Simula is generaly recognized as the first OO language, so it's a second look at the second OO language at best.
- bromagosa 13y ago
  Correct. Although Smalltalk is generally regarded as the first one because the concept "object orientation" was first used in it. Still, the big thing in Smalltalk are not objects, but messages. That's something many later OO languages missed on completely. From Kay: «OOP to me means only messaging, local retention and protection and hiding of state-process, and extreme late-binding of all things. It can be done in Smalltalk and in LISP. There are possibly other systems in which this is possible, but I’m not aware of them.»
  - vidarh 13y ago
    I think the reason many later OO languages "missed" messages completely is because the distinction makes little sense in more static languages that lacks a way to dynamically call a method/send a message.
    - yvdriess 13y ago
      And incidentally, dynamic dispatching is recognised as the key feature of OO: (Cook 2009) Object-oriented programming is successful in part because its key technical characteristic—dynamic dispatch-is essential to supporting independent, interoperating extensions; and because interoperable extension is in turn essential to the reuse of architectural code (as in frameworks), and more broadly to the design of modern software ecosystems.
      - vidarh 13y ago
        I'm not sure if you're agreeing or disagreeing with me. Dynamic dispatch is supported by most statically typed OO languages. C++ virtual member functions are dynamic dispatch. So indeed, dynamic dispatch is one of the key features that makes the distinction between calling methods and sending messages sufficiently un-important that static OO languages are still useful. What was (perhaps too imprecisely) referred to in my comment above is late/dynamic binding.
  - seanmcdirmid 13y ago
    Why would you take Kay's definition of OOP as gospel. To me, OOP is all about thinking and coding in terms of object metaphors. Everything else is a supporting detail.
    - bromagosa 13y ago
      Well, I wouldn't take it as gospel, but as a definition coming from the person who actually invented and first used this term.
      - seanmcdirmid 13y ago
        Alan Kay is very opinionated, I respect his work but don't take him as a god. There are plenty of other people who did much work in OOP in the 70s and 80s who deserve around similar credits for starting up this field, and let's not forget the Scandinavians who actually invented it.
- seanmcdirmid 13y ago
  Simula and to a similar extent SketchPad are proto-OO: they planted the seeds many of the concepts that would go into OO, but Smalltalk is where the seeds were first reaped. But at the end of the day, we are arguing about a label, and its hard to tell where proto-X really becomes X (e.g. anthropologists argue about the line between proto writing and writing).
  - vidarh 13y ago
    I'm curious what you believe Simula is lacking to make it fully OO.
    - seanmcdirmid 13y ago
      See http://www.stanford.edu/class/cs242/slides/2007/simula-smalltalk.pdf http://www.stanford.edu/class/cs242/slides/2007/simula-small.... The main omission is encapsulation.
      - vidarh 13y ago
        Simula does provide encapsulation - it often considered the first language to do so. It does not provide an easy mechanism for information hiding of the encapsulated instance variables. I think that is an exceedingly weak argument against calling it OO, especially as you AFAIK can do information hiding in Simula by using the simulation support that was it's raison-d'etre, namely by using the object lifecycle and co-routine support and starting a method to encapsulate state as part of the class body (constructor, effectively).
        seanmcdirmid 13y ago
        Closures as a form of encapsulation is actually very lispy. Simula introduced classes while Sketchpad introduced prototypes (predates Simula by 5 years), so both were very much proto OO in that sense. But if it makes you feel any better, we could define proto OO just to mean OO before that was a term anyone invented.
stormbrew 13y ago
I feel like a lot of the really clever and elegant things about smalltalk as a language and an object model got bogged down in the program image execution model, to the point where it stunted the evolution of those ideas for a long time. We're getting to the point where such a model is more practical now, but it still strikes me as hopelessly impractical even so. It wasn't until OSX made Objective-C take off and Rails made Ruby take off that some of the fundamental language features entered the mainstream, and they did so with a gusto that other 'ivory tower' languages wish they could achieve. But only by leaving the image model behind. It seems like something like Erlang managed to do what Smalltalk tries to do with the image better, allowing for easier to reason about deployment, collaboration, and version control while still letting you deal with a system of relatively opaque boxes of replaceable code.
- davidw 13y ago
  Funny you should mention Erlang, as I think that in its own way, it's treading the lisp/smalltalk path of getting a few things really, really right, and being head and shoulders better for certain kinds of applications. And yet, at the same time, doomed to sooner or later have enough of its goodies ripped off by programming languages that are more mainstream, that will far surpass it in functionality. Go and Scala, for instance, nabbed some of the concurrency stuff, although Go is still missing some of what makes Erlang really distinct.
  - discreteevent 13y ago
    Dart is trying to rip off Smalltalk and Erlang while putting on Algol sheep's clothing. I have no doubt they will be successful at the Smalltalk part as most of the team seem to be ex-Smalltalkers or ex-Smalltalk VM'ers. I don't know enough about Erlang to know if Dart isolates approximate it.
- bromagosa 13y ago
  But only by leaving the image model behind. There are many Smalltalks without an image actually... GNU-Smalltalk, Smalltalk/X and Amber, for instance. GemStone/S uses a mixture between image and filesystem, so it can't be regarded as a traditional image-based system either. The only Smalltalks that still use an image paradigm (that I know of) are Squeak derivatives (Squeak, Pharo, Cuis) and VisualWorks. That said, I believe the image is a very valid model, and I prefer working on a Pharo environment than anywhere else. However powerful text editors, IDEs and debuggers may be, you can never reach the same level of integration between tools and system if your tools, your language and your system are not the exact same thing.
pjmlp 13y ago
Nice article, but it fails to explain the experience using Smalltalk environment really is. Smalltalk, like Lisp Machines, was originally a blend of GUI operating system, development environment and the first real IDE.
- agumonkey 13y ago
  It's funny. Unix was also meant as an IDE (persistency, logic, machine and user interfaces). It seems they all were trying to reach the same goal in their own way.
  - pjmlp 13y ago
    I never saw UNIX as an IDE, given its command line interface with ed and vi as editors.
    - agumonkey 13y ago
      it's a different user interface paradigm, mainly it's not graphically sophisticated (independent streams of text vs dynamic bitmap overlays)and less time integrated (you have to define how and which script to run when something change). But at the time it was thought so, that's how I felt reading bits of this book http://en.wikipedia.org/wiki/The_Unix_Programming_Environment http://en.wikipedia.org/wiki/The_Unix_Programming_Environmen....
      - pjmlp 13y ago
        My first UNIX experience was in 1993 with Xenix, followed by almost all commercial variants of it. By then I was already spoiled with GUI environments from Atari ST, Amiga 500, Windows 3.x and GEM, as well as the typical MS-DOS IDEs from Borland. So I never saw UNIX that way.
        draegtun 13y ago
        UNIX is my IDE. perl5 is my VM. CPAN is my language. ref: http://shadow.cat/blog/matt-s-trout/but-i-cant-use-cpan/ http://shadow.cat/blog/matt-s-trout/but-i-cant-use-cpan/ | https://news.ycombinator.com/item?id=968757 https://news.ycombinator.com/item?id=968757 NB. Though I think someone else earlier (Audrey Tang perhaps?) made a similar quote (something like CPAN is my syntax?)
mythz 13y ago
There are a number of great answers on StackOverflow as to why Smalltalk wasn't more popular: http://stackoverflow.com/questions/711140/why-isnt-smalltalk-popular http://stackoverflow.com/questions/711140/why-isnt-smalltalk...
deleted 13y ago
[deleted]
Tloewald 13y ago
Simula was the first OO language.
overgard 13y ago
Smalltalk is incredibly cool, but I think one of the main things stunting it is it doesn't have a great free implementation. The only modern smalltalk environment I've used which felt like a serious environment was VisualWorks, and to download that you have to fill out a form and you can only use it under a "personal use" license. Squeak, despite being impressive, has always felt like a toy. I like Pharo in spirit, but GUI wise, it looks really off. If I can use a weird metaphor to describe it: it's like reading a brilliant PhD thesis written in Comic Sans. That's what the GUI reminds me of. The content is brilliant, but the presentation really leaves you scratching your head. I know it's not fair to judge an entire development environment off its aesthetics, but people are going to do it anyway.
- gecko 13y ago
  I get what you're saying, but it's also really weird to me. You cannot sanely use Pharo or Squeak to write native apps right now; that's totally true. You also couldn't do that for Visual Works, except for a very narrow window when they properly emulated enough Windows XP widgets you could probably fake it. But Pharo and Squeak proper look (to me) neither more nor less native than IntelliJ, which people happily use. Both have professional-looking IDEs that do not look native. That doesn't impact you if you're doing web work, command-line work, etc. There are lots of other reasons I would finger instead (C interop was historically poor, people were historically reticent to use VMware-image-like language environments, etc.), but Pharo and Squeak have looked fine for most purposes for awhile.
  - igouy 13y ago
    >You also couldn't do that for Visual Works, except for a very narrow window when they properly emulated enough Windows XP widgets you could probably fake it.< You could always do the work yourself to properly emulate whichever UI look and behavior was needed. (Which was both blessing and curse.) >There are lots of other reasons I would finger instead...< Lack of standardization between vendor implementations.
  - overgard 13y ago
    You're probably right about visual works, I haven't used it since 2005 so I kind of fell in that window. I don't have a problem w/ non-native looking GUI's in principle, but I just think Squeak and Pharo are kinda fugly. Bad spacing, weird colors, weird fonts. If that only effected my development environment I could live with it, but if the apps I make are also going to look like that? Ick. The only thing I'd really use it for is writing games where GUI's are always going to be custom anyway. (I think Smalltalk in general would be great for game development actually.) Another thing is that at least in other smalltalks, it generally used OS windows at least. The controls might look weird, but it does feel like part of the system. Writing code in Squeak feels like you're either using a VM or Remote Desktop, it's just totally isolated. The thing is most of these, in isolation, aren't deal killers, but once you've added up enough weird points it gets a bit too weird. You could make similar arguments about Java, but I think the difference is in magnitude: Java's weirdness is kind of weird, smalltalk's weirdness is really weird.
gecko 13y ago
If you've historically ignored Smalltalk due to its ecosystem or non-native UIs, I'd like to suggest you take a look at Amber (http://amber-lang.net/ http://amber-lang.net/), a Smalltalk that runs on Node and works great for web dev.

77 points by MarcusDenker 13y ago

informatimago 13y ago

Simula is generaly recognized as the first OO language, so it's a second look at the second OO language at best.

bromagosa 13y ago
Correct. Although Smalltalk is generally regarded as the first one because the concept "object orientation" was first used in it. Still, the big thing in Smalltalk are not objects, but messages. That's something many later OO languages missed on completely. From Kay: «OOP to me means only messaging, local retention and protection and hiding of state-process, and extreme late-binding of all things. It can be done in Smalltalk and in LISP. There are possibly other systems in which this is possible, but I’m not aware of them.»
- vidarh 13y ago
  I think the reason many later OO languages "missed" messages completely is because the distinction makes little sense in more static languages that lacks a way to dynamically call a method/send a message.
  - yvdriess 13y ago
    And incidentally, dynamic dispatching is recognised as the key feature of OO: (Cook 2009) Object-oriented programming is successful in part because its key technical characteristic—dynamic dispatch-is essential to supporting independent, interoperating extensions; and because interoperable extension is in turn essential to the reuse of architectural code (as in frameworks), and more broadly to the design of modern software ecosystems.
    - vidarh 13y ago
      I'm not sure if you're agreeing or disagreeing with me. Dynamic dispatch is supported by most statically typed OO languages. C++ virtual member functions are dynamic dispatch. So indeed, dynamic dispatch is one of the key features that makes the distinction between calling methods and sending messages sufficiently un-important that static OO languages are still useful. What was (perhaps too imprecisely) referred to in my comment above is late/dynamic binding.
- seanmcdirmid 13y ago
  Why would you take Kay's definition of OOP as gospel. To me, OOP is all about thinking and coding in terms of object metaphors. Everything else is a supporting detail.
  - bromagosa 13y ago
    Well, I wouldn't take it as gospel, but as a definition coming from the person who actually invented and first used this term.
    - seanmcdirmid 13y ago
      Alan Kay is very opinionated, I respect his work but don't take him as a god. There are plenty of other people who did much work in OOP in the 70s and 80s who deserve around similar credits for starting up this field, and let's not forget the Scandinavians who actually invented it.
seanmcdirmid 13y ago
Simula and to a similar extent SketchPad are proto-OO: they planted the seeds many of the concepts that would go into OO, but Smalltalk is where the seeds were first reaped. But at the end of the day, we are arguing about a label, and its hard to tell where proto-X really becomes X (e.g. anthropologists argue about the line between proto writing and writing).
- vidarh 13y ago
  I'm curious what you believe Simula is lacking to make it fully OO.
  - seanmcdirmid 13y ago
    See http://www.stanford.edu/class/cs242/slides/2007/simula-smalltalk.pdf http://www.stanford.edu/class/cs242/slides/2007/simula-small.... The main omission is encapsulation.
    - vidarh 13y ago
      Simula does provide encapsulation - it often considered the first language to do so. It does not provide an easy mechanism for information hiding of the encapsulated instance variables. I think that is an exceedingly weak argument against calling it OO, especially as you AFAIK can do information hiding in Simula by using the simulation support that was it's raison-d'etre, namely by using the object lifecycle and co-routine support and starting a method to encapsulate state as part of the class body (constructor, effectively).
      - seanmcdirmid 13y ago
        Closures as a form of encapsulation is actually very lispy. Simula introduced classes while Sketchpad introduced prototypes (predates Simula by 5 years), so both were very much proto OO in that sense. But if it makes you feel any better, we could define proto OO just to mean OO before that was a term anyone invented.

stormbrew 13y ago

I feel like a lot of the really clever and elegant things about smalltalk as a language and an object model got bogged down in the program image execution model, to the point where it stunted the evolution of those ideas for a long time. We're getting to the point where such a model is more practical now, but it still strikes me as hopelessly impractical even so. It wasn't until OSX made Objective-C take off and Rails made Ruby take off that some of the fundamental language features entered the mainstream, and they did so with a gusto that other 'ivory tower' languages wish they could achieve. But only by leaving the image model behind. It seems like something like Erlang managed to do what Smalltalk tries to do with the image better, allowing for easier to reason about deployment, collaboration, and version control while still letting you deal with a system of relatively opaque boxes of replaceable code.

davidw 13y ago
Funny you should mention Erlang, as I think that in its own way, it's treading the lisp/smalltalk path of getting a few things really, really right, and being head and shoulders better for certain kinds of applications. And yet, at the same time, doomed to sooner or later have enough of its goodies ripped off by programming languages that are more mainstream, that will far surpass it in functionality. Go and Scala, for instance, nabbed some of the concurrency stuff, although Go is still missing some of what makes Erlang really distinct.
- discreteevent 13y ago
  Dart is trying to rip off Smalltalk and Erlang while putting on Algol sheep's clothing. I have no doubt they will be successful at the Smalltalk part as most of the team seem to be ex-Smalltalkers or ex-Smalltalk VM'ers. I don't know enough about Erlang to know if Dart isolates approximate it.
bromagosa 13y ago
But only by leaving the image model behind. There are many Smalltalks without an image actually... GNU-Smalltalk, Smalltalk/X and Amber, for instance. GemStone/S uses a mixture between image and filesystem, so it can't be regarded as a traditional image-based system either. The only Smalltalks that still use an image paradigm (that I know of) are Squeak derivatives (Squeak, Pharo, Cuis) and VisualWorks. That said, I believe the image is a very valid model, and I prefer working on a Pharo environment than anywhere else. However powerful text editors, IDEs and debuggers may be, you can never reach the same level of integration between tools and system if your tools, your language and your system are not the exact same thing.

pjmlp 13y ago

Nice article, but it fails to explain the experience using Smalltalk environment really is. Smalltalk, like Lisp Machines, was originally a blend of GUI operating system, development environment and the first real IDE.

agumonkey 13y ago
It's funny. Unix was also meant as an IDE (persistency, logic, machine and user interfaces). It seems they all were trying to reach the same goal in their own way.
- pjmlp 13y ago
  I never saw UNIX as an IDE, given its command line interface with ed and vi as editors.
  - agumonkey 13y ago
    it's a different user interface paradigm, mainly it's not graphically sophisticated (independent streams of text vs dynamic bitmap overlays)and less time integrated (you have to define how and which script to run when something change). But at the time it was thought so, that's how I felt reading bits of this book http://en.wikipedia.org/wiki/The_Unix_Programming_Environment http://en.wikipedia.org/wiki/The_Unix_Programming_Environmen....
    - pjmlp 13y ago
      My first UNIX experience was in 1993 with Xenix, followed by almost all commercial variants of it. By then I was already spoiled with GUI environments from Atari ST, Amiga 500, Windows 3.x and GEM, as well as the typical MS-DOS IDEs from Borland. So I never saw UNIX that way.
      - draegtun 13y ago
        UNIX is my IDE. perl5 is my VM. CPAN is my language. ref: http://shadow.cat/blog/matt-s-trout/but-i-cant-use-cpan/ http://shadow.cat/blog/matt-s-trout/but-i-cant-use-cpan/ | https://news.ycombinator.com/item?id=968757 https://news.ycombinator.com/item?id=968757 NB. Though I think someone else earlier (Audrey Tang perhaps?) made a similar quote (something like CPAN is my syntax?)

mythz 13y ago

There are a number of great answers on StackOverflow as to why Smalltalk wasn't more popular: http://stackoverflow.com/questions/711140/why-isnt-smalltalk-popular http://stackoverflow.com/questions/711140/why-isnt-smalltalk...

deleted 13y ago

[deleted]

Tloewald 13y ago

Simula was the first OO language.

overgard 13y ago

Smalltalk is incredibly cool, but I think one of the main things stunting it is it doesn't have a great free implementation. The only modern smalltalk environment I've used which felt like a serious environment was VisualWorks, and to download that you have to fill out a form and you can only use it under a "personal use" license. Squeak, despite being impressive, has always felt like a toy. I like Pharo in spirit, but GUI wise, it looks really off. If I can use a weird metaphor to describe it: it's like reading a brilliant PhD thesis written in Comic Sans. That's what the GUI reminds me of. The content is brilliant, but the presentation really leaves you scratching your head. I know it's not fair to judge an entire development environment off its aesthetics, but people are going to do it anyway.

gecko 13y ago
I get what you're saying, but it's also really weird to me. You cannot sanely use Pharo or Squeak to write native apps right now; that's totally true. You also couldn't do that for Visual Works, except for a very narrow window when they properly emulated enough Windows XP widgets you could probably fake it. But Pharo and Squeak proper look (to me) neither more nor less native than IntelliJ, which people happily use. Both have professional-looking IDEs that do not look native. That doesn't impact you if you're doing web work, command-line work, etc. There are lots of other reasons I would finger instead (C interop was historically poor, people were historically reticent to use VMware-image-like language environments, etc.), but Pharo and Squeak have looked fine for most purposes for awhile.
- igouy 13y ago
  >You also couldn't do that for Visual Works, except for a very narrow window when they properly emulated enough Windows XP widgets you could probably fake it.< You could always do the work yourself to properly emulate whichever UI look and behavior was needed. (Which was both blessing and curse.) >There are lots of other reasons I would finger instead...< Lack of standardization between vendor implementations.
- overgard 13y ago
  You're probably right about visual works, I haven't used it since 2005 so I kind of fell in that window. I don't have a problem w/ non-native looking GUI's in principle, but I just think Squeak and Pharo are kinda fugly. Bad spacing, weird colors, weird fonts. If that only effected my development environment I could live with it, but if the apps I make are also going to look like that? Ick. The only thing I'd really use it for is writing games where GUI's are always going to be custom anyway. (I think Smalltalk in general would be great for game development actually.) Another thing is that at least in other smalltalks, it generally used OS windows at least. The controls might look weird, but it does feel like part of the system. Writing code in Squeak feels like you're either using a VM or Remote Desktop, it's just totally isolated. The thing is most of these, in isolation, aren't deal killers, but once you've added up enough weird points it gets a bit too weird. You could make similar arguments about Java, but I think the difference is in magnitude: Java's weirdness is kind of weird, smalltalk's weirdness is really weird.

gecko 13y ago

If you've historically ignored Smalltalk due to its ecosystem or non-native UIs, I'd like to suggest you take a look at Amber (http://amber-lang.net/ http://amber-lang.net/), a Smalltalk that runs on Node and works great for web dev.